Mars Orbiter Glitch Stalls Red Planet Science

NASA's Mars Reconnaissance Orbiter passes over the planet's south polar region in this artist's concept illustration. The orbiter's shallow radar experiment, one of six science instruments on board, is designed to probe the internal structure of Mars' polar ice caps, as well as to gather information planet-wide about underground layers of ice, rock and, perhaps, liquid water that might be accessible from the surface. Phobos, one of Mars' two moons, appears in the upper left corner of the illustration. ImageCredit: NASA/JPL/Corby Waste

NASA?s Mars
Reconnaissance Orbiter has suffered an apparent glitch that has left the spacecraft
in a protective safe mode and stalled science observations as it circles
the red planet, the space agency announced late Wednesday.

The malfunction
occurred on Monday when the orbiter unexpectedly rebooted its main computer and
entered safe mode, an automatic safeguard designed to protect the spacecraft
from further damage when it detects a glitch.

NASA
engineers are reviewing potential causes for the malfunction aboard the
Mars Reconnaissance Orbiter (MRO) in the hopes of resuming
its science observations of the red planet.

"We
are going to bring the spacecraft back to normal operations, but we are going
to do so in a cautious way, treating this national treasure carefully,"
said MRO project manager Jim Erickson at NASA's Jet Propulsion Laboratory,
Pasadena, Calif. "The process will take at least a few days."

The Mars orbiter?s
malfunction occurred Monday at about 7:25 a.m. EST (1225 GMT), when the
spacecraft was flying behind the red planet as seen from Earth. While MRO has suffered
glitches that put it in safe mode five times since its 2005 launch, Monday?s malfunction
does not resemble any of those earlier glitches, NASA officials said.

An initial
analysis suggests that the malfunction may have been caused by the
detection of a power surge that lasted between 200 nanoseconds and 41 seconds.
The power surge may have been real, or it could have been a phantom reading,
mission managers said.

One theory
is that the MRO
spacecraft may have been hit by a cosmic ray, causing an erroneous power
surge reading for about nine microseconds, more than enough time to trigger the
computer reboot, mission managers said.

MRO flight engineers
managed to partially revive the spacecraft late Monday, when they boosted its
communication rate from 40 data bits per second to a level some 10,000 times
faster. The spacecraft?s batteries are charged and its expansive solar wings are
generating electricity, mission managers said.

Launched in
August 2005, the MRO spacecraft is NASA's youngest orbiter in a fleet of spacecraft circling the red planet. It arrived in orbit around Mars in October 2006 to begin a planned two-year
mission. The spacecraft?s initial $720 million mission has since been extended by
two more years to 2010.

During its
time at Mars, MRO has beamed home stunning vistas of the red planet and tracked
NASA?s twin rovers Spirit and Opportunity as they explore the Martian surface.

The
spacecraft has also used its high-resolution camera to scout for future Martian
landing sites and spotted
NASA?s most recent probe - the Phoenix Mars Lander - as it parachuted down
to a pinpoint landing on the planet?s arctic plains in May 2008.